Panicked by late-night realization of a missing valuable, we bolted out of our home a few months ago, returning to find messages on our home line and cell phones. I knew without checking voicemail that we forgot to disarm the security system before leaving, and that ADT had been trying to reach us. Looking out the window, Seattle Police Department officers were making their way up the steps.

The good news: Proof that the security alarm worked exactly as designed.

The bad news: We owed $115 for the false alarm.

But more good news: You can get a one-time waiver of the fee by taking a “False Alarm Reduction Workshop.”

The class is held monthly (call 206-684-7713 for information) at SPD headquarters in downtown Seattle. It’s basically a 75-minute Powerpoint presentation plus time for questions, and it’s actually fairly interesting. I learned that in 2010, there were over 14,000 alarm calls. Of these, only 223 were valid alarms, resulting in 19 arrests.

With 98% of alarm dispatches being false, the cost to the city is over $1 million per year. Okay, now I see why we get charged for false alarms.

The 25 of us in the class also learned about block watches, crime prevention through environmental design (CPTED)—dealing with lighting and landscaping, and physical security issues (door lock and window consideration. I left the class knowing I should trim some hedges, improve my motion sensor lighting, and be more careful about not triggering another false alarm. That $115 refund will be going toward some home improvements in the near future.